Snap-action electrical switch having planar terminals mounted in a common plane



June 1965 H. R- CHAPIN ETAL 3,

SNAP-ACTION ELECTRICAL SWITCH HAVING PLANAR I TERMINALS MOUNTED IN A COMMON PLANE Original Filed May 27, 1959 2 Sheets-Sheet l Fla. 2.

Fae. l0

F I 6. I2

INVENTOR.

HowAln R. CHAPIN Joann J. KAI-EBA Y Arronusy June 15, 1965 E H. R. CHAPIN ETAL SNAP-ACTION ELECTRICAL SWITCH HAVING PLANAR TERMINALS MOUNTED IN A COMMON PLANE Original Filed May 2'7, 1959 2 Sheets-Sheet 2- INVENTOR. HowARo R. CnnPm J'osEPH d. mesa United States Patent This application is a continuation of application Serial No. 816,189, filed May 27, 1959 and now abandoned.

This invention relates to electrical switches and more particularly to an improved snap action precision switch and a process for mass-producing such switches.

Precision snap action switches require accurate pivot and anchor points to assure proper alignment of the parts to provide precise operation of the switch. Formerly switches of this nature had relied on a combination of stamped and formed parts to complete the finished product. While accuracy and uniformity are inherent in stamped parts over extended production, forming tools are relatively inaccurate and do not have precision necessary to provide consistent snap action in the switch.

The primary object of this invention is to Provide a switch which is fabricated largely of stamped parts which are so arranged as to lend themselves readily to high production without adjustment.

Another object of this invention is to provide a switc in which all of the critical parts are inherently properly aligned.

A further object of this invention is to provide a process for fabricating a snap action switch which will insure the accurate location of contacts and supports during final assembly.

A still further object is to provide a switch in which the base of the housing is molded around the blade contact supports and can be molded in multiple units to greatly decrease fabricating costs.

A final object of this invention is to provide a switch which can be easily ganged.

Other objects and advantages will be pointed out in, or be apparent from, the-specification and claims, as will obvious modifications of the single embodiment shown in the drawings in which:

FIG. 1 is a side elevation partly in section of a complete snap action switch;

FIG. 2 is a plan view of a switch with the cover removed;

FIG. 3 shows the first step in the process showing the terminal strip;

FIG. 4 shows the terminal strip with the contacts in place;

FIG. 5 shows the terminal strip with the upper portion trimmed oif;

FIG. 6 shows the terminal strip with the plastic body molded thereon;

FIG. 7 shows the terminal strip with the lower portion trimmed oif;

FIG. 8 is a view taken on line 8-8 of FIG. 1;

FIG. 9 shows aplurality of switches mounted on a single bar;

FIG. 10 is taken on line 1tl10 of FIG. 1;

FIG. 11 shows a modified form of contact; and

FIG. 12 shows another modified form of contact.

Referring to the drawings, FIGS. 1 and 2 show the complete switch contemplated by the invention. The switch includes terminals 10', 12 and 14, plastic body 16, blade 18, stationary contacts 20 and 22, and a cover 24 supporting an actuating button 26.

The terminals 10, 12 and 14 are first stamped in a 3,189,73 Patented June 15, 1965 unit which is part of a metal strip in which any number of units can be stamped simultaneously. The units are retained in strip form to reduce handling and thereby eliminate individual fabrication. Each unit includes terminals 10, 12 and 14, upper web 28, lower web 30, anchor 32 and pivot 34. Contact supporting slots 36 are also stamped in each unit.

Silver contacts and 22 are then mounted (FIG. 4) in the slots 36 by peening the divergent portion of the contact into the slot. This provides a rigid fit that will not be easily displaced. Where a lower amperage operation is contemplated the contacts may be modified to use brass points 40 (FIG. 11) stamped with the original strip or circular slugs 43 (FIG. 12) also peened into appropriate curved slots. These contacts can be peened simultaneously along an entire strip of units without distorting the contact points due to the presence of the webs 28 and 30.

The upper web 28 is then trimmed (FIG. 5) from each unit in a single operation on the strip. The upper ends of the terminals 10, 12 and 14 are then separated one from the other with the blade anchor and pivot being an integral part of terminal 10. Upper contact 20 is integral with terminal 14 and lower contact 22 is integralwith terminal 12.

The terminal strip is set in a multiple mold and the body 16 is molded to each unit in the strip. The terminals are still connected by web 30 and need not be separately jigged during the molding operation. Each unitis provided with a number of holes 42 forth'e plastic to flow through to hold the terminals in place.

The lower web is then trimmed, FIG. 7, from the unit, leaving the terminals 10, 12 and 14 insulated one from the other. Simultaneously with this step the adjacent body units are separated from each other leaving each switch an independent unit.

Blade 18, FIG. 2, which has been separately stamped is next secured to the anchor and pivot. Anchor 32 is inserted through slot 44 in the mounting tongue 46 and is swedged to make a rigid fit. The compression tongue 48 is then inserted into pivot 34 so that the contact end 50 is forced against upper contact 20. The accuracy of the switch is increased because the anchor, pivot, contacts and terminals are all in one plane omitting the necessity of providing for side forces.

An actuating button 26 is inserted through a hole 52 in cover 24 and retained in the cover by head 54. The cover, preferably a resilient thermoplastic, is then snapped onto rail 56 provided along the sides of the body 16, FIG. 8, and slot 58 formed on the inside of the cover fits over the contact end of the terminal 14 to prevent it from being misaligned.

To operate the switch, the button 26 is depressed against bridge 60 of the blade. The rails 62 will move downward until a point is reached where the force of the compression tongue on the contact end will be reversed to snap the contact end down against the lower contact, closing the circuit through terminal 12 and opening the circuit through terminal 14. When the button is released, the bridge will move upward, again reversing the force of the compression tongue on the contact end and snapping the end up against the upper contact, opening the circuit through terminal 12 and closing the circuit through terminal 14.

Where a multiple switch installation is required, the switches can be easily ganged by sliding a bolt or bar 66 through hole 68 provided in the body. A lug 69 and recess 70 provided on the sides of the body will interlock to form a unitary ganged structure as shown in FIG. 9. Thus the locating lug and recess arrangement permits gauging the switches with use of only one bolt or the like.

Reference is hereby made to the co-pending applications of Messrs. Howard R. Chapin and Joseph I. Kaleba, Serial Nos. 280,487 and 280,488, both of these applications having been filed on April 26, 1963, both applications being entitled Snap Action Switch. and Process for Making the Switch. and both being divisional applications of this application. These divisional applications relate to and claim the process of manufacturing the switch of this application and to the above described construction which permits ganging the switches, both of these features being disclosed but not claimed in this application.

Although but one embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from. the spirit of the invention or from the scope of the appended claims.

We claim:

1. A snap action switch including a body, three planar plane, thefirst terminal member including a blade mount and pivot, the second and third terminal members each including a contact, and a blade secured to the mount on the first terminal member and extending between the contacts on the second and third terminal members and engaging the. pivot on the first terminal member so that the blade can be moved into engagement with one or the other of saidcontacts.

3. A snap action switch including a body, three planar terminal. members mounted in the body in a common plane, the first terminal member including a blade mount, the second and third terminal members each including a contact slot, a silver contact secured in each slot, and a blade mounted on the first terminal member and extending between the contacts on the second and third terminal members for making contact with one or the other of the contacts.

4. A snap action switch including a body, three planar 45 terminal members mounted in the body in a common plane, the first terminal member including a blade mount,

the second and third terminal members each including a divergent contact slot, a pair of silver contacts each having a divergent end and each secured in one of said divergent slots, and a blade mounted on the first terminal member and extending between the silver contacts on the second and thirdterminal members for making contact with one or the other of the contacts.

5. A snap action switch including a body, a plurality of terminal means molded in said body, one of said terminal means defining a blade mount and second and third terminal means each .including a contact, and a blade mounted on said blade mount and extending between the contacts on the second and third terminal means for making contact with one or the other of said contacts, each of said terminal means. being characterized by a planar configuration so that said terminal means are, free of formed portions.

6. A snap action switch including a body, three terminal members in said body, the first terminal member including a blade mount and pivot, the secondand third terminal members each having a contact, and a blade secured to the mount on the first terminal member and extending between the:contacts on the second and third terminal members and engaging the pivotonthe firstterrninal member so that the blade can be moved into engagement With oneor the other of said contacts, each of said terminal members characterized by a planar configuration so that said terminal, means are free, of formed portions.

FOREIGN PATENTS 345,901 4/56 Great Britain. BERNARD A. GILHEANY, Primary Examiner.

ROBERT K. SCHAEFEKExaminer. 

1. A SNAP ACTION SWITCH INCLUDING A BODY, THREE PLANAR TERMINAL MEMBERS MOLDED IN THE BODY IN A COMMON PLANE, THE FIRST TERMINAL MEMBER INCLUDING A BLADE MOUNT, THE SECOND AND THIRD TERMINAL MEMBERS EACH INCLUDING A CONTACT, AND A BLADE MOUNTED ON THE FIRST TERMINAL MEMBER AND EXTENDING BETWEEN THE CONTACTS ON THE SECOND AND THIRD TERMINAL MEMBERS FOR MAKING CONTACT WITH ONE OR THE OTHER OF THE CONTACTS. 